JP3440343B2 - Torque calibration device for electric valve drive - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque calibrating device for a motor-operated valve drive machine, which is adapted to calibrate a preset torque in the motor-operated valve drive machine used in, for example, a power plant.

[0002]

BACKGROUND OF THE INVENTION power plant or the like, have been used a number of the valve device, in order to drive it, et al,
For example, an electric valve drive machine (hereinafter simply referred to as a valve drive machine) (A) as shown in FIG. 3 is used.

In this valve drive machine (A) , a worm shaft oriented in the front-rear direction (for convenience, the right side in FIG. 3 is the front side and the left side is the rear side) is provided in the approximate center of the box-shaped housing (B).
(1) is pivotally supported.

The worm shaft (1) has a plurality of spur gears (2) (3).
Via a reduction gear mechanism (4) composed of the like and a clutch mechanism (5), the motor (electric motor) (6) provided at the rear portion of the housing (B) is linked, and the operation of the motor (6) causes Forward and reverse rotation (hereinafter, rotation in the direction of closing the valve body in the valve device described later for convenience, is referred to as forward rotation, and rotation in the same opening direction is also referred to as reverse rotation), and through a pair of spur gears (7) and (8) It is also linked to a handle shaft (10) provided with a handle (9) for manual operation, and can be rotated forward and backward by rotating the handle (9) with the clutch mechanism (5) disengaged. It has become.

[0005] worm shaft (1) is a worm (11) is, by spline coupling, and is fitted in the axial direction relative movable and rotationally fixed. At the front end of the worm shaft (1), the sleeve (12) cannot move axially relative to the worm (11) , and the worm shaft (1) and the worm (11) cannot move.
This sleeve is provided so that it can rotate relative to
A torque balance spring (13) composed of a plurality of disc springs for urging the worm (11) in the axial direction is externally fitted to the (12).

Worm wheel that meshes with the worm (11)
(14) is integrally formed on the outer circumference of a cylindrical stem nut (15) that faces the vertical direction, and the female screw (15a) engraved on the inner surface of the stem nut (15) has a vertical direction. Facing Valve Axis (16)
A male screw (16a) formed on the upper part of the is screwed. Valve stem
At the lower end of (16), the valve body (17) in the valve device (not shown)
There are connected, the valve shaft (16) is vertically movable only, and is held unable to rotation about the axis. Therefore,
When the worm (11) rotates without moving in the axial direction, the worm wheel (14) and the stem nut (15) are integrally rotated in the forward and reverse directions, and the female screw (15a) and the male screw (16a) at that time are rotated. The valve shaft (16) and the valve body (17) are integrally lowered and raised by the screwing of the valve shaft (16) and the valve body (17) to close and open the valve device.

A worm wheel (18) meshes with a small worm (1a) carved on a relatively rear portion of the worm shaft (1),
Rotation speed detection axis (18a), which is the axis of the worm wheel (18)
Is linked to a valve opening control device (19) for freely setting the upper and lower limits of the valve shaft (16).

The pinion (20) meshes with the rack (12a) formed on the outer periphery of the rear portion of the sleeve (12), and the torque detection shaft (20a) which is the shaft of the pinion (20) is a valve body. (17) when the torque for opening and closing reaches a predetermined set value, more precisely, when the set value is reached the movement amount in the axial direction of the worm (11) is predetermined, stopping the operation of the motor (6) The torque control device (22) is provided with a rotary type torque limit switch (21).

In such a conventional valve drive machine (A), when the worm shaft (1) is normally rotated by the motor (6), the worm (11) is rotated in the same direction as the worm shaft (1) is rotated in the normal direction. The worm wheel (14) is stopped by the friction resistance on the valve shaft (16) side, and the worm (11) and sleeve (12) are moved in the axial direction. Compressed. The axial biasing force of the worm (11) due to the compression of the torque balance spring (13) causes the valve shaft (16) to move.
When the frictional resistance of the worm (11) becomes larger than the frictional resistance of the worm (11), the axial movement of the worm (11) and the sleeve (12) is stopped, and all the rotational force of the worm (11) is transmitted to the worm wheel (14). 14) and the stem nut (15) are integrally rotated in the forward direction, the valve shaft (16) and the valve body (17) are integrally lowered, and the valve device is closed.

[0010] When valve body (17) is such as tucked foreign matter in the middle valve is closed, and increases lowered resistance of the valve shaft (16), normal rotation is stopped the worm wheel (14) , Meanwhile, the worm (11) and the sleeve (12) are moved in the axial direction,
The torque balance spring (13) is further compressed from the above state. The amount of compression of this torque balance spring (13), that is, the amount of movement of the sleeve (12) in the axial direction, is a preset value.
When the set torque is reached, the torque limit switch (21)
There actuated, the forward rotation of the motor (6) is stopped, the motor
The image sticking of (6) is prevented.

[0011]

As described above, in the conventional valve drive machine (A), the disc springs constituting the torque balance spring (13) are displaced by the rack (12a) and the pinion (20). The torque balance switch (13) is used to convert the rotation angle and the rotary torque limit switch (21) detects overload.
Or cause "sag" in disk spring constituting the, if you or cause depletion to the sliding portions of the components, the torque set value predetermined by the torque limit switch (21), actual torque limit switch ( There is a discrepancy with the torque when 21) operates. Therefore, the torque limit switch (2
It is necessary to periodically Calibration the set value of 1). At that time, the conventional actuates actually motor (6), since the calibration work overload has been performed on the valve body (17), the work is complicated, labor is disadvantageously consuming. Further, depending on the usage status of the valve device in the plant, there are some cases in which the valve can not be opened / closed for inspection and regular calibration work cannot be performed.

In view of the above problems of the prior art, the present invention can easily calibrate the set torque without actually driving the motor or overloading the valve body. It is an object of the present invention to provide a torque calibrating device for a motor-operated valve drive machine , which enables the above.

[0013]

In order to achieve the above object, the invention according to claim 1 is such that a worm is axially supported on a worm shaft pivotally supported in a housing so as to be rotated forward and backward by an electric motor. A torque balance spring that urges the worm in the axial direction between the worm and the housing, and a worm wheel and a valve shaft that mesh with the worm. A torque limit switch is provided which is linked to open and close the valve by the forward and reverse rotations of the wheels and further which stops the operation of the electric motor when the amount of movement of the worm in the axial direction reaches a predetermined set value. In the motor driven valve drive, the direction of the axis with respect to the worm
To the sleeve that is linked as
The torque balance spring consisting of a disc spring and the spring
And a pair of spring bearings, and
The range of movement of the spring bearing is limited to the shoulders and three
And limit it with the nut that is screwed to the tip of the
The moving range of both spring supports with respect to the housing.
Between the shoulder on the housing and the load cell on the support.
In addition, a load meter that detects the urging force of the worm in the axial direction by the torque balance spring is provided on the support body provided in the housing so that the position of the worm can be adjusted in the axial direction. There is.

According to a second aspect of the present invention, in the above-mentioned device, the support is brought into contact with the tip of the sleeve,
Pushing that can push the worm axially through the sleeve
It is characterized in that the body is provided so that its position can be adjusted in the axial direction of the worm .

The invention according to claim 3 is the apparatus according to claim 2.
Position, a male screw is engraved on the outer periphery of the pusher, and the male screw is
Is a screw hole facing the axial direction of the worm formed in the support.
By screwing the pusher onto the support,
It is possible to adjust the position in the axial direction of the
A non-circular hole is bored, and a housing and a support are provided in the non-circular hole.
Non-circular shaft formed at the tip of a tool inserted through the body
So that the pusher can be rotated by the tool by engaging the parts.
It is characterized in the thing.

The invention according to claim 4 is the same as claims 1 to 3.
The device according to any one of the above, wherein the sleeve has a female end at the end thereof.
And engraving the thread, screwing it into the female screw,
A volute that extends through the housing and faces the worm axis.
With the bolt, and abuts on the outer surface of the housing
The worm and pull the worm toward the load cell.
It is characterized in that a pulling means for pulling is formed .

The invention according to claim 5 is the same as in claims 1 to 4.
In the device described in the offset, it is characterized in that the housing is provided with a displacement gauge for measuring the displacement amount of the worm in the axial direction.

The invention according to claim 6 is the device according to claim 5.
Position, the displacement gauge is screwed onto the tip of the sleeve.
Abut on the spring bearing that contacts the
By measuring the displacement of the worm in the axial direction,
The feature is that the displacement amount of the worm in the axial direction is measured .

[0019]

[Function] The support provided on the housing is positionally adjusted in the axial direction of the worm, and by the load cell supported by the support,
By detecting the urging force of the worm in the axial direction by the torque balance spring, it is possible to directly measure the actual urging force of the torque balance spring when the torque limit switch is operated, that is, the torque that is actually operated. If this value differs from the set torque, as they match, again setting the torque limit switch, i.e. to calibrate.

[0020]

Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a state when calibrating the torque in the closing direction, and FIG. 2 shows a state when calibrating the torque in the opening direction. Since the configuration other than the portions shown in FIGS. 1 and 2 is the same as the conventional one shown in FIG. 3, illustration and description thereof are omitted, and the same members as the conventional one are the same. Description will be given with reference numerals.

In FIG. 1, the cylinder portion (31) forming a part of the housing (B) is provided with a male screw portion (32b) on the outer periphery of the front end portion of the reduced diameter portion (32a) and the reduced diameter portion (32a). ) The sleeve (3) in which the enlarged diameter part (32d) is connected to the rear end via the shoulder part (32c)
2) is on the same axis as the worm shaft (1), housing (B)
And the worm shaft (1) so as to be movable in the front-rear direction.

At the center of the front end of the sleeve (32), a female screw (32e) used for calibrating the torque in the opening direction shown in FIG.
Has been drilled. The front end of the worm shaft (1) is loosely fitted to the rear part of the sleeve (32), and the worm shaft (1) is
In addition, the front end of the worm (11), which is externally fitted movably and rotatably in the axial direction via the plain bearing (33), is attached to the inner surface of the expanded diameter portion (32d) via the ball bearing (34). Supported Sleeves (32)
Can move axially with the worm (11).

A rack (35) meshing with the above-mentioned pinion (20) is formed on the outer peripheral surface of the enlarged diameter portion (32d) of the sleeve (32), and the torque detecting shaft (20a) which is the shaft of the pinion (20). ), The amount of movement of the sleeve (32) and the worm (11) in the axial direction is detected, and finally the drive torque of the valve body (17) is detected.

In the reduced diameter portion (32a) of the sleeve (32), a torque balance spring (13) composed of a plurality of disc springs (36) and a pair of spring bearings (37) (37) 38) and are externally fitted so as to be slidable in the axial direction. The axial movement range of both spring bearings (37) (38) relative to the sleeve (32) is
Shoulder portion provided in 2) and (32c), the external thread portion of the sleeve (32) (32 b)
It is limited by the nut (39) which is screwed into. Also,
The axial movement range of both spring bearings (37) and (38) with respect to the housing (B) is determined by the shoulder portion (40) provided on the inner surface of the cylinder portion (31).
When the cylinder unit (31) disposed a ring-shaped load cell in the (4
1) Limited by and. With this configuration, the urging force of the torque balance spring (13) is
From the state shown in FIG. 1, (11) can act both in the backward valve closing direction and in the forward valve opening direction.

The load cell (41) is for detecting the axial urging force of the worm (11) by the torque balance spring (13), and is a known one using a strain gauge (not shown) or the like. It is often supported by a piston-like support body (42) slidably arranged in the front-rear direction in the cylinder portion (31) of the housing (B).

The support body (42) is provided with three or other appropriate number of guide rods (43) penetrating the front end face of the cylinder part (31) slidably and at the center of the front end face of the cylinder part (31). Screwed into the drilled screw hole (44), the rear end abuts the front surface of the support (42) ,
A push bolt (45) that can push the support (42) backward and a small-diameter screw hole (46) drilled in the eccentric part of the front end face of the cylinder part (31) are screwed together to form a rear end. The position adjustment means (48), which comprises a plurality of stop bolts (47) whose parts are brought into contact with the front surface of the support body (42), enables position adjustment in the axial direction of the worm (11). There is.

A through hole (49) having a large diameter screw hole (49a) formed in the rear portion is formed in the center of the support body (42), and the sleeve (32) is formed in the screw hole (49a). ), The male screw (50a) formed on the outer circumference of the pusher body (50), which is one of the worm moving means capable of pushing the worm (11) backward through the sleeve (32), is screwed. I am fit. Pusher (50)
A square or other non-circular hole (51) is bored in the center of the screw hole (44) and the through hole (49) after the push bolt (45) is removed. Through the cylinder part
(31) Non-circular shaft formed on the tip of the tool inserted in
By engaging (not shown) and rotating the pusher body (50) by the tool, the rearward protrusion amount of the pusher body (50) with respect to the support body (42) can be adjusted.

[0028] (52), the outer periphery of the main body of the sensor unit (52a) and the male screw, the displacement gauge stylus (52 b) was made to rise from, the distal end (rear end) of the body (52a), the body The front part of (52a) is screwed into a small-diameter screw hole (53) formed in an eccentric part of the front end face of the cylinder part (31), and is fixed by a lock nut (54). 42) by fitting Yu a through hole (55) bored in the eccentric portion of, and parallel to the support and the axis of the sleeve (32), and protrudes from the rear end of the <br/> body (52a) probe (52b) to the front spring plate
(37) in contact with the front surface of, by measuring the amount of movement in the longitudinal direction of the receiving the spring (37), which was set to be indirectly measured displacement in the axial direction of the c Omu (11) Is.

The numerals in FIG. 2 (56), when calibrating the opening direction of the torque, in place of the push bolts (45) shown in FIG. 1, in one of the worm moving means that will be mounted to the cylinder portion (31) in some attracted means, the rear end portion to the internal thread (32e) which is engraved before the end of the sleeves (32) are screwed, and the support (4
Through-holes of 2) (49) and the cylinder portion of the screw hole (44) in (31) through a worm (11) bolts (57) facing an axial, is screwed to the bolt (57), And the worm (11) that is made up of the nut (58) that abuts on the front end surface of the cylinder part (31 ).
The acts to draw forward toward the sleeve load meter via a (32) (41).

Next, the procedure for calibrating the torque in the closing direction will be described with reference to FIG. First, the push bolt (45)
With the tool removed, press the pusher (50) with a tool not shown.
The Rotate, as shown in FIG. 1, with the load meter (41) is in contact with the receiving front of the spring (37), between the front end rear end and the sleeve (32) of the pusher (50) The amount of rearward protrusion of the pusher body (50) with respect to the support body (42) is adjusted so that a minute gap is formed.

Next, screw the bolt (45) pushed screw hole (44), by pressing the support at its rear end (42) to the rear, pushers (5
The rear end of 0) is brought into contact with the front end of the sleeve (32), and the front of the spring receiving (37), pushed by the load meter (41) the nut (39)
At a slight distance from, the displacement gauge (52) is reset to the zero point.

After that , by further screwing the push bolt (45) , the pusher body (50) moves the sleeve (32) and the load cell.
(41) forward of the spring in the receiving (37), push each rearward simultaneously
You The rearward movement of the sleeve (32) at this time rotates the pinion (20) and its shaft, the torque detection shaft (20a).
To do. This rotation causes the torque limit switch (21)
When the (see Fig. 3) is activated, the push bolt at that point
Stop screwing (45) and read the measured values of load cell (41) and displacement meter (52) at that time.

When the measured value of the load meter (41) at this time is different from the set torque , the push bolt (45) is further screwed in until the measured value of the load meter (41) matches the set torque, or Or, conversely, the screw is returned, and the torque control device (22) side is readjusted so that the torque limit switch (21) operates at the position of the sleeve (32) at that time. That is, calibrate.

Further, by comparing the measured value of the displacement gauge (52) during the operation of the torque limit switch (21) with the measured value of the calibrated displacement gauge (52), the torque balance spring (13) The amount of settling can be known, and the settling of the torque balance spring (13) over time can be known by constantly recording these measured values.

In this embodiment, the pusher body (50) and the displacement gauge are
Although (52) is used, calibration can be done without them. For example, instead of using the pusher (50),
With the valve shaft (16) shown in Fig.
The worm shaft (1) is normally rotated by manually rotating (9), and the sleeve (32) is moved in the axial direction by the axial movement of the worm (11) at this time, and the torque limit switch (21) is moved. ) Actuated, stop the rotation of the handle (9) and then screw in the push bolt (45) until the front spring bearing (37) is slightly separated from the nut (39) .
The load cell (41) is pressed against the front spring receiver (37), the measured value of the load cell (41) at that time is read, and thereafter, the calibration may be performed in the same manner as described above.

The displacement gauge (52) is a torque balance spring.
This is useful for accurately knowing the displacement amount of (13) and performing high precision calibration, but if high precision is not required, this can be omitted and carried out.

Next, the procedure for calibrating the torque in the opening direction will be described with reference to FIG. In this case, the push bolt (45) of FIG. 1 is removed, and the pusher body (50) is rotated by a tool (not shown) so as to be immersed in the support body (42) as shown in FIG.

Next, the support bolt (42) is stopped by the stop bolt (47 ).
Position the load cell (41) on the front spring seat (37).
Brought into contact, and be slightly separated received ahead of the spring (37) from the nut (39).

After that, the bolt (57) of the attracting means (56)
The screw holes (44), through holes (49) and non-circular holes (51) in sequence.
Turn on,Bolt (57)Tip,On the tip of the sleeve (32)
Screw it into the female screw (32e) and screw it into the bolt (57).
Contact the nut (58) with the front end face of the cylinder (31).Let
It

[0040] Next, a Rukoto rotate the bolt (57)
The sleeve by turning only the nut (58).
(32) gather pull forward. Then , the worm (11) and the rear spring receiver (38) also move forward together with the sleeve (32), and the torque balance spring (13) is compressed.

When the torque limit switch (21) is operated by the forward movement of the sleeve (32), the rotation of the nut (58) is stopped at that time, and the load meter (41) at that time is stopped.
Read the measured value of.

The measured value of the load meter at this time (41), the nut so when different from the set torque, to the measurement value of the load meter (41) coincides with the set torque, the bolt (57) moves forward and backward
(58) is rotated, and the torque control device (22) side is readjusted so that the torque limit switch (21) operates at the position of the sleeve (32) at that time. That is, calibrate.

In the above embodiment, the single torque balance spring (13) can apply the urging force to the worm (11) in both directions. In the case where the worm is biased only in one direction, or in the case where such torque balance springs are symmetrically arranged on both sides of the worm,
The set torque can be calibrated only by the means shown in either FIG. 1 or FIG.

The position adjusting means (4) for the support (42) described above is also used.
8) and the pulling means (56) are those which use screwing of bolts, but may be, for example, hydraulic jacks or other means.

[0045]

According to the present invention, the following effects can be obtained. (a) The set torque can be easily and accurately calibrated by observing the measurement value of the load cell without actually driving the electric motor or applying an overload to the valve body ( contract).
Invention of claim 1 ).

[0046] (b) when performing calibration of the set torque, it is not necessary to disassemble the electric valve drive motor, has a simple calibration procedure, calibration may occur at any time or frequently set torque (claim 1 ).

(C) Stop the load cell on one spring bearing
When used as a valve, it acts when the valve is actually opened or closed.
The torque can be monitored (the invention according to claim 1) .

(D) If a pusher is provided on the support,
The worm can be moved by the position adjusting means of
The worm by other means when calibrating the set torque.
The workability is improved without the need to make it (claims 2 and 3).
Inventions listed) .

(E) A non-circular hole is formed in the pusher body, and
Insert the non-circular shaft formed at the tip of the tool into the pusher
It is convenient to be able to adjust the position of
Invention described in 3) .

(F) The worm is loaded by the pulling means.
If you pull it toward the weight scale, the torque balun
The compression direction of the spring and the placement of the load cell are different.
The present invention can be applied even in such a case, increasing versatility.
(Invention according to claim 4) .

(G) The pulling means is composed of a bolt and a nut.
The simple structure makes it possible to reduce the cost.
(The invention according to claim 4) .

(H) Measuring the displacement of the worm in the axial direction
If you install a displacement meter that
Etc. can be accurately known, and highly accurate calibration can be performed.
It is possible (the invention according to claims 5 and 6) .

(I) The position adjusting means of the support is pushed
If it is configured with a bolt (45) and a stop bolt (47), the structure will be
Simple and convenient (Example) .

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view of essential parts showing a state when calibrating torque in a closing direction of an electric valve drive machine according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional side view of essential parts showing a state when the torque in the opening direction is calibrated.

FIG. 3 is an overall perspective view showing a conventional electric valve drive machine with a part cut away.

[Explanation of symbols]

(A) Valve drive (B) Housing (1) Worm shaft (1a) Small worm (2) (3) Spur gears (4) Reduction gear mechanism (5) Clutch mechanism (6) Motor (7) (8) Spur gears (9) Handle (10) Handle shaft (11) Warm (12) Sleeve (12a) Expanded part (12b) Reduced diameter part (13) Torque balance spring (14) Worm wheel (15) Stem nut (15a) Female thread (16) Valve shaft (16a) Male screw (17) Disc (18) Worm wheel (18a) Rotation speed detection axis (19) Valve opening control device (20) Pinion (20a) Torque detection axis (21) Torque limit switch (22) Torque control device (31) Cylinder section (32) Sleeve (32a) Reduced diameter part (32b) Male thread (32c) Shoulder (32d) Expanded part (32e) Female thread (33) Plain bearing (34) Ball bearing (35) Rack (36) Disc spring (37) (38) Spring support (39) Nut (40) Shoulder (41) Load cell (42) Support (43) Guide rod (44) Screw hole (45) Push bolt (46) Screw hole (47) Stop bolt (48) Position adjustment means (49) Through hole (49a) Screw hole (50) Pusher (Worm movement means) (50a) Male screw (51) Non-circular hole (52) Displacement meter (52a) body (52b) Stylus (53) Screw hole (54) Lock nut (55) Through hole (56) Pulling means (worm moving means) (57) Bolt (58) Nut

Claims (6)

(57) [Claims] 1. A worm shaft, which is rotatably and reversely rotated by an electric motor, is fitted onto a worm shaft pivotally supported in the housing so as to be relatively movable in the axial direction and non-rotatable, and the worm and the housing. A torque balance spring that urges the worm in the axial direction is provided between
And the worm wheel that meshes with the worm and the valve shaft,
Provided with a torque limit switch that works together to open and close the valve by forward / reverse rotation of the worm wheel, and stops the operation of the electric motor when the amount of movement of the worm in the axial direction reaches a predetermined set value. In the motor driven valve drive, the worm cannot be moved relative to the worm in the axial direction.
The torque which consists of a plurality of disc springs in the engaged sleeve
Fitting a balance spring and a pair of spring receivers that sandwich the spring
The moving range of both spring supports with respect to the sleeve.
A nut that is screwed onto the shoulder of the sleeve and the tip of the sleeve.
Space between the housing and the
The range of movement of the blade receiver is limited to the shoulder and the support provided on the housing.
The urging force in the axial direction of the worm by the torque balance spring is detected by the support body provided in the housing so that the position can be adjusted in the axial direction of the worm. A torque calibrating device for a motor-operated valve drive machine, comprising a load cell. 2. The support is brought into contact with the tip of the sleeve.
Pushes the worm axially through the sleeve
Position of the movable pusher can be adjusted in the axial direction of the worm.
To the torque calibration apparatus of an electric valve drive motor according to claim 1, wherein the provided. 3. A male screw is engraved on the outer periphery of the pusher body to form the male thread.
Screw facing the axial direction of the worm formed in the support.
By screwing the pusher into the hole,
The position of the pusher can be adjusted in the axial direction of the arm.
A non-circular hole is formed in the
Non-circular shape formed at the tip of the tool inserted through the holder
The pusher can be rotated by the tool by engaging the shaft.
Torque Calibration apparatus for an electric valve drive motor according to claim 2, wherein a was Unishi. 4. A female screw is engraved on the tip of the sleeve,
It is screwed into the female screw and penetrates the support and housing.
Through the bolt, facing the axial direction of the worm, and the bolt
To the nut that is screwed into and comes into contact with the outer surface of the housing.
Pulls the worm toward the load cell
4. The method according to claim 1, wherein the means is formed.
Torque Calibration apparatus for an electric valve drive motor crab according. 5. The torque calibration device for a motor driven valve drive machine according to claim 1, wherein the housing is provided with a displacement gauge for measuring the displacement of the worm in the axial direction. 6. A displacement gauge is screwed onto the tip of the sleeve.
Abut the spring bearing that is in contact with the nut, and
By measuring the axial displacement of the armor worm,
To measure the axial displacement of the worm.
The torque calibration device for a motor-operated valve drive machine according to claim 5 .